Age-related changes in mutagen activation by rat tissues.
Age-related changes in drug metabolism of the liver, lung and kidney of adult female Long-Evans rats were determined by measuring changes in mutagen formation. Activation of aflatoxin B1 (AFB1), 2-aminofluorene (AF) and 2-acetylaminofluorene (AAF) to mutagenic derivatives was assayed using the Ames Salmonella test system. The promutagens were incubated with tissue fractions from rats ranging in age from 2.5 to 25 months. With all three compounds, hepatic, renal and pulmonary activation was lower in the senescent than in the young adult animals. The largest decrease, however, occurred prior to middle-age, i.e. before 9-13 months. In liver and kidney, little change was detectable between the middle-aged and the old (20-25 months) animals. However, pulmonary metabolism in the oldest animals was slightly higher than in the extracts from the middle-aged rats. The observed decline in mutagen activation may thus be a function of maturation rather than senescence.
D015073:2-Acetylaminofluorene / Q000378:metabolism*; D016604:Aflatoxin B1; D000348:Aflatoxins / Q000378:metabolism*; D000375:Aging; D000818:Animals; D001711:Biotransformation; D005260:Female; D005449:Fluorenes / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D008168:Lung / Q000378:metabolism; D051381:Rats
D000348:Aflatoxins; D005449:Fluorenes; C012177:2-aminofluorene; D015073:2-Acetylaminofluorene; D016604:Aflatoxin B1